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astroengine writes "For the first time, scientists have found direct evidence of the expansion of the universe, a previously theoretical event that took place a fraction of a second after the Big Bang explosion nearly 14 billion years ago. The clue is encoded in the primordial cosmic microwave background radiation that continues to spread through space to this day. Scientists found and measured a key polarization, or orientation, of the microwaves caused by gravitational waves, which are miniature ripples in the fabric of space. Gravitational waves, proposed by Albert Einstein's General Theory of Relativity nearly 100 years ago but never before proven, are believed to have originated in the Big Bang explosion and then been amplified by the universe's inflation. 'Detecting this signal is one of the most important goals in cosmology today,' lead researcher John Kovac, with the Harvard-Smithsonian Center for Astrophysics, said in a statement."

Thank you for posting that link. This is fascinating but they left out the most important question: does the Lattice run on ESX or Hyper-V? We already know it can't be VMware workstation because the product won't let one install an hypervisor inside a VM (I tried).

My point is: try installing VMware workstation in a VM created with VMware workstation. It does not work. Ergo, since I can install VMware workstation in the "real world" it means that the "real world" is not a VM running on VMware workstation.

The Lattice HAS to run on ESX or Hyper-V, unless Root has access to a better technology. Maybe Sun LDOMs?

In any event I hope it's not an organic/slimy technology like those pods in Existenz.

There is no center. The expansion happens everywhere at once. A mediocre but helpful analogy is to the surface of an expanding balloon. Imagine drawing a bunch of dots on the surface. As the balloon expands, every dot moves farther from every other dot. There is no center -- or rather, *every* point looks like a center.

(Note that in this analogy, the universe is the *surface* of the balloon only. The 3D expansion of the balloon has a center, but the 2D stretching of the surface does not. It's a bit confusin

A direct detection of a gravitational wave moving the mirrors of a large scale interferometer is up next. In the next few years, Advanced LIGO (US), Advanced Virgo (Italy) and KAGRA (Japan) will come online with the hope of directly detecting gravitational waves from sources such as supernovae and coalescing binary star systems. With this kind of network, it will then be possible to coordinate both electromagnetic and gravitational searches of our sky. This is useful for many reasons, one of which is that it lets us listen to the sound of black holes colliding where no light escapes.

A direct detection of a gravitational wave moving the mirrors of a large scale interferometer is up next. In the next few years, Advanced LIGO (US), Advanced Virgo (Italy) and KAGRA (Japan) will come online with the hope of directly detecting gravitational waves from sources such as supernovae and coalescing binary star systems. With this kind of network, it will then be possible to coordinate both electromagnetic and gravitational searches of our sky. This is useful for many reasons, one of which is that it lets us listen to the sound of black holes colliding where no light escapes.

Actually no. Hawking radiation doesn't actually leave a black hole, it's created at the event horizon when vacuum fluctuations create a particle/antiparticle pair, one of which falls into the black hole while the other escapes. As the net mass-energy of such pairs is zero, and the (distantly) observed mass-energy of the escaping particle will be positive (it exists), the observed mass-energy of the captured particle must be negative. Thus when the black hole captures the particle it loses mass rather tha

nice...was going to post this but I wouldn't have explained it as well...

honest quesiton: do you think what you described is commonly understood among physicists? It seems to me, and I of course could be wrong, that alot of stuff I see on/. is conflating what happens *on the event horizon* with the actual black hole itself

I even got into a discussion with the editors of the Black Hole wiki...the first sente

I believe so. My understanding is that in physicist circles the black hole starts at the event horizon. For many you could say it ends there as well, since physics as we know it can't exist within the horizon. Hawking radiation meanwhile originates just outside the event horizon, not on it. Basically the "virtual particles" are continuously spontaneously created at ever point in the universe, but mostly self-annihilate immediately - Hawking radiation is simply a case of half of a pair being captured bef

Are you a physicist, or have you seriously studied physics, or do you have a source for that? Because I'm sure I've read numerous times about actual physicists hoping to detect gravity waves from merging black holes.

It's not contradictory. The black holes will dump a metric giga-fuckton of energy as gravity waves before merging (it's science, so we have to use these new-fangled metric units). Once they merge, well, the established theory is that no energy could escape but that's being challenged more often these days. AFAIK, no one every actually detected Hawking radiation and everything predicted about black hole decay is untested, so having any detector that can observe a black hole merger will tell us a bunch!

To go even further, I believe Hawking himself recently came to the conclusion that black holes don't actually exist - the even horizon would be unstable creating more of an "event twilight zone" that would sometimes be within the limit and sometimes not, allowing material in the "suddenly not" region to escape. And a black hole from which things can escape is no black hole at all.

For most astronomical purposes "supermassive non-luminous objects" would essentially be black holes, just lacking an event horizon (which to my knowledge we still have precious little observational evidence for). Of course since the event horizon is *the* defining quality of a black hole, the astronomical similarity is irrelevant.

I agree that Hawking's new objection is a fair bit more subtle than that though.

It would not be possible to detect gravity waves (or anything else) from a source inside a black hole. Here we are talking about gravity waves created when two black holes interact.

Imagine to non-black holes - say neutron stars colliding (boom!). As they collide the gravitational field around them varies rapidly ( changes from 2 sources to a single source). Those variations send "ripples' (gravity waves) through space. The ripples aren't just from inside of the neutron stars, but from the fields which extend outside. If you now collide black holes, the same thing happens, gravity (and curvature of space) near the black holes changes radically as they collide and some of that is emitted as gravity waves.

The above is of course a hand-wave. The *real* answer is that you can simulate the Einstein field equations as the black holes collide, and they show the radiation of gravitational wave.

You would move a really heavy object and measure when some other object gets affected by the changed gravity from the new position. Alas, to get a good measurement it would be handy to accelerate something with at least the mass of a planet to a small percentage of light speed.

I am sure astronomers will figure out how to use a natural event instead, but as far as I know that has not happened yet.

Once you have a working (direct, not the one on TFA) detector for gravity waves, you just need a second one and a pair ver very well synchronized clocks. That'll let you calculate the speed of the waves.

we'll see. If it's SoL, then that means space remain bent even after the object causing the bend is gone; which has some interesting implication.If i's instant, the that also has some very interesting implications.

Speed of light is the fastest the universe allows information to propagate. Gravitational waves cannot move faster than light can because its not light that is the limit, but the UNIVERSE. Light doesnt go faster because the universe limits it.

You're a decade early. What you say is *true* but the relevant time would be the late 1910s when Einstein was applying general relativity (1915) to cosmology and introduced the cosmological constant to engineer a static universe.

inflation - a particular period of rapid expansion immediately after the big bang.

"Rapid" doesn't really do it justice; if I've understood the theories (or rather, the analogies of the theories) correctly the expansion was equivalent to an object the size of a proton swelling to 10^19 light years across, in just 10^-33 seconds.

Also, and yet again I may be misunderstanding the analogies of the theories (I'm very far from being a cosmologist), the size of the observable universe was roughly 3 metres at that point; the whole universe was about 10^23 metres across - so it grew a fair bit in

I guess the answer really is twofold; for one, everything is moving apart from everything else, so two objects moving apart on directly opposed vectors could do so at very, very close to the speed of light and the combined speed of separation for an external observer would be almost twice the speed of light, and secondly that the speed of light "limit" is for things travelling through the universe, not the fabric of the universe itself.

There are three problems in cosmology that inflation solves: flatness: the universe is very close to its critical density, the horizon problem: the universe looks like it is in thermal equilibrium for no good reason, and absence of magnetic monopoles.

Note that this the second indirect evidence for the existence of gravitational waves, the first one was the orbital decay of a binary system that included a pulsar, discovered by Hulse and Taylor [wikipedia.org] (Nobel Prize 1993 [nobelprize.org]). Today's result, if confirmed, seems pretty spectacular, and might be rewarded with a second Nobel Prize. For a first direct detection of gravitational waves, we have to wait for first detections by LIGO [ligo.org], Virgo [virgo.infn.it] and eLISA [elisascience.org].

Some interesting perspective [profmattstrassler.com] from Matt Strassler, who's a particle physicist at Harvard.

He points out that this is still an *indirect* observation of gravitational waves (and not the first one) and that the results look sensibly in line with some predictions from inflation. And that while this is a tremendous experiment, it's not any kind of "smoking gun", and we really need to wait for replication to get properly excited.

Incorrect. Or, rather, been shown to be false by the evidence. And it was such a damn elegant model, too.
Bravo to the team of researchers who've been working a decade on this satellite and these observations. I believe Neil and another scientist had a small bet about this, so he's also out of pocket a few dollars. Now we just have to hypothesise new ideas that will eliminate the many kludgy math bits out of Big Bang model.
This news, and 120 more BlackBerry jobs lost today, means a sad day here in Waterl

You evidently have a different definition of "elegant" to me. My definition of "elegant" does not include "theories containing hand-crafted and unjustified potentials of a strikingly bizarre form inserted purely phenomenologically into a theory that is a phenomenological attempt to see what might happen if some facets of M theory are put onto large scales". That's not to defend inflation too much but the potentials of inflatons are typically quadratic or quartic,

Did you hear that? That was the sound of millions of religious zealots pressing their palms harder against their ears and screaming LA LA LA even louder.

I'll bite. I'm sure you'd consider me a "religious zealot." I believe in God. I believe in the Bible for what it is---a religious text that has suffered at the hands of multiple translations, compilations, and shenanigans, but that still has managed to retain the essential doctrines of man's relationship to God. It is not, and was never intended to be, a scientific text. The account in Genesis merely says that in six "days" (the original Hebrew word means "time periods") God instructed that the earth should be created, and that this creation was carried out through some unspecified agency. I don't believe God has thrown in CMB and dinosaur bones to deceive us, because I believe that he is a God of truth. My faith certainly doesn't drive me to deny science, because science is (or at least should be) ultimately a search for truth, and all truth brings us closer to the God of truth. The Bible is an excellent spiritual resource that has enhanced my relationship with God, but it tells me very little about physics, engineering, and biology.

So please tell me how your faith---which I assume dictates that the universe is a convenient sequence of coincidences, each individually of staggering improbability, and all of them taken together forming something at least as incomprehensible as the most convoluted beliefs about God---is inherently more reasonable than my faith, which is that there is a creative genius operating in all the majesty of creation.

First of all, how is it that all stars moving apart from each other rapidly is not "first direct evidence" of the universe's expansion? And secondly, how could the expansion of the universe amplify gravitational waves? Space stretching would thin out the waves because they would be expressed over a wider area. Also, you don't create more gravity without adding mass or energy. Neither is occurring due to universe expansion, and of course the fact that mass and energy can't be "created" under any circumsta

"First of all, how is it that all stars moving apart from each other rapidly is not "first direct evidence" of the universe's expansion?"

Because it isn't. The first direct evidence of the universe's expansion is typically accredited to Hubble in the 1920s and was very firmly established a good couple of generations back. Don't believe all you read in/. summaries...

"And secondly, how could the expansion of the universe amplify gravitational waves? Space stretching would thin out the waves because they would

I think you have it wrong. You see, these creationists...they have a book which describes exactly how the world was created. It is called the Bible and it states pretty clearly how it happened. The problem here is that this so called "evidence" contradicts the very strong evidence they have...namely, their book.

Since it contradicts their book by claiming to take billions of years, it must (by very definition) be wrong. So what you really have is the Big bang is a bad interpretation of the natural world.

I met a guy from Sri Lanka once who had the best comment yet on "Prayer in schools":"I am perfectly ok with prayer in schools, and I would encourage it but it seems a bit impractical if they don't already have an altar to catch the blood."

The word typically translated "day" or "days" in Genesis is originally "Yowm" (root meaning "hot"). Strong's translates this variously as "period"—it's a very general term that I usually read as "era".

My limited understanding is that most of Jesus' contemporaries believed in an ancient universe. It was Ussher's bestseller that, ahem, fixed that problem.

I don't know why you need to go arguing about all these fancy foreign words; if English was good enough for Jesus then it should be good enough for us to understand his teachings. You think if he wanted us using Hebrew words, he would have written the bible in it.

Well, Catholic schools (at least the one I went to) regularly teach evolution in their biology classes, amongst other things. They are hardly the same groups that push this anti-science BS (anymore), shit they even appologized to Galileo (after 400 years.... so they are....slow...)

While I have plenty I am happy to lambast the Catholics over; I have to hand it to them....they don't really push the creationism as we have come to know and despise. In fact, while you may find lay Catholics with all manner of be

Time to play:Name that logical fallacy!Would that be: argument form authority?Ding ding ding, we have a winner.

Why do you think just becasue they are a priest they know what the Bible means?I went to catholic school, and I constantly pointed out error in priest beliefs. Hell, most of them don't even know their own theology, much less it's history.A previous pope talked about this:http://en.wikipedia.org/wiki/T... [wikipedia.org]

The silliest part of it is where the book comes from. The bible is a creation of a committee of the early catholic church that sat down with more than 1500 spiritual texts and decided on 300 that were important enough to include in a book given to all priests. Now ask a young earth creationist what they think of the catholic church and the typical response is the whore of Babylon, yet the book they so revere as the accurate word of god was creating by a committee of early members of the catholic church. It'

I have video proof that a runaway queen can freeze her whole country and create a giant ice castle in less time than a pop song.My kids strongly believe it's really cool, therefore global warming science is wrong.

I am going to assume you missed the recent evolution debate with Bill Nye where his opponent actually attempted, on several occasions, to claim the Bible explained several things that Nye claimed we still can't explain.

If people want to use the Bible as a bunch of allegorical stories on how to live, more power to them. However, when they actually try to claim that it explains things science cannot or that other explanations must be wrong simply because they contradict the bible (which, some do);

Basically sifting through information gathered from older CMB detectors, they discovered a statistical B-mode [slashdot.org] in the data that could have come from gravitational wave that occurred during inflation, but the data was really too noisy to be sure.

The new news is they used a new detectors [caltech.edu] which are capable of making cleaner measurements to convince themselves that the detected B-mode was unlikely to come from gravitational lensing after the big-bang. The current evidence apparently is consistent with the B-mode coming from a gravitational waves that are predicted to occur during the inflationary period of the universe.

The AC may be referring to results from the Planck observatory (see, e.g., planck.caltech.edu/publications2013Results.html), which put some constraints on the inflationary era. What is interesting is the results that were released today may not completely agree with the Planck data. It is too early to say if the disagreement is real or not.

Well, it does say about commanding their hosts. Physics has nothing to say about whether or not the universe had their hosts commanded during inflation, so this could be a valuable addition to our knowledge.

Radio waves still have polarisation, just the same as optical and gamma radiation does. You need some pretty refined equipment to study it in detail but you can build it. Check out bolometers and radiometers.

Who do you think predicted the gravitational radiation in the first place? There's a reason we've been wanting to find them since the 1990s and it's not that observational cosmologists were arguing with theoreticians that they were definitely there.

"A viable alternate theory is that light gives up some energy while traveling extremely long distances, which shows up as red-shift. Where does the energy go? It could be the source of energy for the CMBR. It could go somewhere else. In any case, as a theory, it explains the red-shift just as well as expansion."

Excellent! Now repeat the rest of the predictions of the Lambda CDM model. Ah, no, you'll have trouble with that one.

"Another viable alternate theory is that the absorption/emission spectra of atoms differs with space/time. Perhaps atoms farther away or longer ago created and absorbed light at lower frequencies, this making older light appear red-shifted by current frequency comparisons. This theory is even harder to test, but just as good at explaining the observations. "

Even better! Now repeat the rest of the predictions of the Lambda CDM model. I think you'll have problems with that one, too.

Actually, I'll give you a bye -- all I want to see is the position of the first peak on the CMB *and* the wavelength of the oscillations in the large-scale structure, with one predicted consistently from the other. Once you've done that, if you can further get out supernovae 1a redshift/distance plots I'll give you extra credit, but since the progentiors aren't fully understood I'll give you a bye on that one, too.

See, the word "viable" has certain caveats. It has to satisfy the observations it's been built to explain *at least* as well as the theory it's replacing. Second, it has to -- self-consistently -- predict further observations that fit *at least* as well as the theory it's replacing. I'm no fan of Lambda CDM but its successes should convince anyone who's actually looked seriously at them that there's something close to reality there, even if ultimately it's a phenomenology close to reality (which it is; I can prove it's phenomenology -- rigorously -- but I can't demonstrate how wrong it actually is, and neither can anyone else at present, but I can at least assert that up until very recent times it's so close as to be indistinguishable and no that I fit all observations, and even very recently it's exceedingly good).

"if I'm allowed to make stuff up whenever I want to make my theory fit the model, I can do at least as well as the Lambda CDM"

Go ahead - you're more than welcome to. Empty assertions don't show much but new cosmological models are welcomed. *I* welcome them, anyway; I've never liked Lambda CDM much and it's obviously a phenomenological model. But they have to be predictive, and founded on firm principles.

I didn't actually want to suggest you're an idiot because I think it's apparent you're not, but this type of post at the same time implies that *cosmologists* are idiots and brainwashed into a model that doesn't really make much sense. And in some cases that's actually true -- there are more and more cosmologists trained into cosmology rather than general relativity and it's a bit dangerous -- but on the whole I don't think many people *like* LCDM. There are too many unanswered questions in it, and everyone is looking to answer those. Just some people work more tightly within its framework than others.

"is there a point where you would ever consider reexamining the questions of the assumptions? Why haven't we reached that point yet?"

Oh, don't misunderstand me -- I *constantly* question and re-examine the assumptions. At some point, if you're genuinely interested, flip back through my posts on Slashdot; I've made my position I think fairly clearly. Boiling it down and putting it in bullet form it goes something like this:

* The "big bang theory", and Lambda CDM in particular, is an astonishingly successful theory, particularly when attached to an inflationary period in the early universe or something that mimics its observational results closely* The successes of Lambda CDM -- such as the predicted abundances from Big Bang nucleosynthesis, the *prediction* of the angular power spectra of the CMB (temperature auto-correlation, temperature/E mode cross correlation, E mode polarisation auto-correlation and now the B mode polarisation auto-correlation) from a simple early primordial power spectrum, the direct mapping between the wavelength of the sound horizon at last scattering as seen on the CMB and that same wavelength imprinted on large-scale structure and *observed* as the baryon acoustic oscillations, and their ilk -- are far too numerous and significant to be ignored.* Any alternative absolutely has to preserve these, and they're all extremely sensitive* Lambda CDM is wrong. It is dead wrong. It is wrong in principle. It is questionable from a particle physics perspective, particularly where it comes to dark energy, but far more importantly, it cannot be justified with general relativity.

Lambda CDM rests on a few main assumptions:
* The universe is on average isotropic around the Earth. OK, fine, we can't argue that; the CMB is proof enough.
* Since the Earth is nowhere special, the universe is on average isotropic around every point: homogeneous. Well, this is debatable since the Earth *is* in a particular position, but on the whole this is probably at least approximately true.
* Gravity is best described on large scales (ie > mm) by a metric theory. This is currently practically unquestionable; metric-based theories of gravity are vastly more succesful than any alternative.
* Gravity is described by general relativity. OK, now we're entering questionable territory but GR remains our best example of a metric-based theory and is yet to be seriously challenged (though there are many, myself among them, who point out that the appearance of dark matter on galactic scales, and the addition of dark energy on cosmological scales, may very well imply that actually we cannot apply gravity on such scales or else that it simply doesn't act this way on large scales)
* GR can be applied directly on large scales. This is extraordinarily shaky. Actually, it's unjustifiable. We've got two main objections here: firstly, there is no reason to assume that gravity actually obeys GR on large s

Thank you for sharing your perspective like a gentleman. I respect that.

I think the core of our disagreement is with your expectation that all the things explained by LCDM must be explained by other theories. I believe it's perfectly fine for the answer to be that some things aren't connected. If we no longer assume we know the age of the universe, then predictions of element ratios no longer need to agree with observations of CMB, which may be totally disconnected from galaxy supercluster clumpiness. If r